I have ordered a QLG2 module and am reading the data provided by Hans thoroughly to understand how it works and how it is set up (something that it seems a lot of people do not bother to do with? QRP Labs kits!).

One thing which I was struggling with was the instruction data for the GK9501 chip set used in the GPS receiver.? I managed to make some sense using "Google Translate", but it was hard going.

With further help from Google, I found an English language version of the document here:?

I think the compilers of that document probably themselves used "Google Translate", as the English is a little quaint in places.? (For example, use of the word "star" instead of "satellite".)
However, it may be of some use to others trying to get the receiver to do exactly what they want it to!

--
Peter Lee
G3SPL

On 03/02/2023 17:39, G3SPL wrote:

I found an English language version of the document here: <>

Peter,

I do not think I've seen that, thanks.

A while ago I did something similar to you

I'm not sure it really was of much use but an interesting exercise:-)

73 Alan G4ZFQ

Having looked at that English version more carefully, it raises more questions than it answers!? For example, if you look at command 151, it says that Galileo is not supported in this firmware level. This despite it having a 2021 date in the footer.? All other documentation implies that Galileo does work, so I suspect that this document is really a bit earlier than the date says.

Anyway, there are 2 assumptions I am working on at the moment.? Firstly, I assume that commands are remembered in NVRAM so whatever state is set up is held over a power cycle.? The second is that it works in the same way as QLG1, namely that the serial NMEA sentences reflect the time at the PREVIOUS one second (PPS) pulse.? I would be grateful if someone could confirm these assumptions!? ?By the way, I am working towards my own version of a shack clock, with an Arduino Uno and LCD display.
--
Peter Lee
G3SPL

On 04/02/2023 17:04, G3SPL wrote:

it says that Galileo is not supported in this firmware level.

Peter,

With the one I tested (and I do not think the QLG2s I now have are different) Galileo worked, my notes give restrictions of combinations.

I assume that commands are remembered in NVRAM so whatever state is set up is held over a power cycle.

As Hans says, no. I *think* a proper backup battery does hold settings.

NMEA sentences reflect the time at the PREVIOUS one second (PPS) pulse.

This is always the case. Early GPS model NMEA displays have shown over 1 second behind real time.

73 Alan G4ZFQ

开云体育

Is that something to do with the PPS being for "the second I'm now telling you about on the serial interface, but which you haven't fully received yet"?

Blow me, it gets curiouser and curiouser...? I've now found yet another document:?.

This mentions another command, number 121 (not covered in the Chinese language doc).? It says as follows:

It clearly mentions "flash" memory.? (Command 115 in the same doc says "does not save to flash").? So I am now thinking that other commands might be saved.? I am particularly interested in the sentence type output - at present I want to restrict output to the RMC and possibly GSV sentences.? Anyway, I will have fun testing it when it arrives!? Thanks for the help.

--
Peter Lee
G3SPL

On 05/02/2023 00:21, G3SPL wrote:

I've now found yet another document: It clearly mentions "flash" memory.

Peter, Willie

Ebyte seem to be progressing!
However, be careful. This document seems to refer to a built E108-GN02 module, not the basic GPS "chip".
Where is this flash memory? I suspect it is on the module board, not the basic chip.

In my opinion far more suitable for experimenting is the u-Blox V-KEL module . It is still available at just over 7 UKP.

This has an English configuration program and manual. It has the flash to save settings and as a bonus the PPS output can be configured to give up to about 15MHz output. (Not a particularly clean signal, a NCO with GPS accuracy.)


On 04/02/2023 21:02, William Smith wrote:

Is that something to do with the PPS being for "the second I'm now
telling you about on the serial interface, but which you haven't fully
received yet"?

Willie,

I'm certain the NMEA follows the PPS. I started being interested in GPS modules about 20 years ago when I discovered the Rockwell Jupiter that had a GPS disciplined 10KHz output, ideal for controlling a PLL.
These ones were relatively slow. The NMEA at 4800 baud followed the PPS.
In those days establishing fairly accurate time from time signals was relatively easy. All analogue, no SDRs or digital broadcasts to add very significant delays. I guess I'm remembering those days when I say more than a second delay for the NMEA display.
Saying that seems a good way of showing accurate time on a computer.

73 Alan G4ZFQ